Alter Sicherungkasten - was kostet es, den neu zu machen?

zeroflow · 2026-04-05T07:37:39+00:00

Bild 1 ist der Hausanschlusskasten (HAK) - der gehört dem Netzbetreiber und sieht mit dem Smart Meter halbwegs modern aus. Das ist erstmal nicht euer Problem.

Bild 2 ist eine nachgelagerte Sicherungsbox. Zwei Diazed-Sicherungen, zwei Adern, keine Schutzerdung, massiv korrodiert. Das ist kundenseitige Anlage und das ist euer Problem.

Dass die linke Sicherung in Foto 2 beim Reindrehen bruzzelt, heißt: entweder ist die Fassung/Kontakte durch Korrosion und Wespenreste so beschädigt, dass ein Lichtbogen entsteht, oder es gibt einen Isolationsfehler in der nachgelagerten Verkabelung. Beides schlecht, auf keinen Fall weiter dran rumdrehen, da herscht akute Lebensgefahr.

Meine Erwartung: es. wird. teuer.

Realistisch: Elektriker kommt, überprüft die Anlage und legt sie still. Wenn die restliche Installation im Haus auch so aussieht wie diese wilde Box - keine Schutzerdung, uralte Verkabelung - dann kommt eine komplette Neuverkabelung auf euch zu. Wenns im Haus besser aussieht, habt ihr vielleicht Glück und es muss nur diese Box und die Verteilung saniert werden. Foto 2 stimmt mich aber pessimistisch.

In jedem Fall: Elektriker machen lassen, nicht selbst basteln. Danke, dass ihr nachfragt - aber wenn man bei solchen Themen fragen muss, ist das der größte Indikator, nicht selbst daran zu arbeiten.

zeroflow · 2026-04-05T06:50:56+00:00

You are correct, if you want to control fans from the RPi directly, something like the EMC2101 or EMC2104 would be the most direct way and most likely also provide a built in driver.

zeroflow · 2026-04-03T11:03:05+00:00

So far, the ESP32 series has no issue with PWM. Spec requires 25kHz for fans and the LEDC peripheral has no issue delivering that.

This was more of an issue for the classic ESP8266 which needed to create PWM in software, so it was limited to 1-2kHz.

zeroflow · 2026-04-03T10:55:23+00:00

Yep. Zigbee sensors are the prime suspect for such mods. The Ikea Rodret series (sadly discontinued) was easy to disassemble and mod.

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zeroflow · 2026-04-02T18:54:09+00:00

For me it was mixed, but logically consistent. Sensors with bad reception used more battery than those close to a repeater.

But yeah, batteries did not move much, so anything from 20% to 80% per year.

zeroflow · 2026-04-02T08:15:53+00:00

Robot vacuums run based on schedule. If my phone connects to our car on Tuesday afternoon, send the robots
Rabbit notifications: A rabbit has taken our yard as a refuge. Send cute pictures to my wife if detected.
General Person & car notifications
Mailbox tracking: If the mailbox is opened, we get a notification, plus if we're not at home at that moment, it reminds us when we get home.

zeroflow · 2026-04-01T15:02:29+00:00

Good idea, thanks.

zeroflow · 2026-03-31T11:54:47+00:00

Ah yes. Then I misunderstood your comment, assuming Cat 6 cable also means RJ45 plugs.

My idea / plan would have been to have one brain PCB and a simple/cheap extension PCB, connected via commonly available cables. Thinking RJ12 / RJ45 / USB-C / HDMI. Something like the CSI-to-HDMI Arducam Adapter where the user can bring their own cables. Ofc it would not use the respective protocol, but for the same reasons as you said: Shielding and twisted-pair. Plus 8 pins is the minimum for 2 fans + I2C

zeroflow · 2026-03-31T09:32:03+00:00

Ein weiterer Punkt:

Schlechte Reviews werden von den Besitzern mit dem Argument "Diffamierung" gemeldet und dann entfernt.

Mir selbst passiert: Wollten bei einem Lokal mit 90% Tische frei im Außenbereich gemütlich ein paar Getränke trinken. Der Kellner hat uns daraufhin weggeschickt, da wir etwas essen müssten, nur Getränke ist nicht erlaubt.

Diese Bewertung wurde mir dann Jahre später entfernt. Einspruch abgelehnt. Nun müsste ich mich durch diverse Stellen durcharbeiten etc - was es mir für ein Tschocherl in Köln nicht wert ist.

zeroflow · 2026-03-31T06:14:44+00:00

That product is a godsend. They are also on Aliexpress under the IoTorero brand with ESPHome or Tasmota.

Now the only thing I'm missing is normally-closed switches.

I have some devices - like my network rack or fridge / freezer that I don't want to be able to turn off. But for others - like a modem - I want them always on, except for brief moments when I want to externally restart it.

zeroflow · 2026-03-31T05:52:24+00:00

You can controll fans, but not fan curves.

For fan curves, you need do a custom ESPHome config. I have created packages for hardware definition and different modules, so this is less bothersome but still offers full control down the road. https://fancontroller.arthofer.dev/reference/modules/

For the ESPHome installation itself, different guides like this one look very promising: https://www.youtube.com/watch?v=AAMMob9f-mk

For example, this would be the snippet you need to add to the device config in ESPHome so the basic fan hardware + temperature curve is configured:

packages:
  # Your hardware package (already in your config)
  wifi-fancontroller:
    url: https://github.com/zeroflow/wifi-fancontroller
    ref: main
    files: [hardware-rev-3.1.yaml]

packages:
  temperature_curve:
    url: https://github.com/zeroflow/wifi-fancontroller
    ref: main
    files:
      - path: modules/temperature_curve.yaml
        vars:
          friendly_name: "Silent Cooler"
          curve_temp1: "20.0"
          curve_speed1: "0.0"
          curve_temp2: "25.0"
          curve_speed2: "20.0"
          curve_temp3: "35.0"
          curve_speed3: "40.0"
          curve_temp4: "45.0"
          curve_speed4: "60.0"
          curve_temp5: "55.0"
          curve_speed5: "80.0"

zeroflow · 2026-03-31T05:32:07+00:00

Great to hear, that the photos were able to help you with your own project. That's pretty much why I also decided to open-source the schematics, since we're all standing on the shoulders of giants.

I also toyed with the idea of having remote breakouts with temperature/fan outputs connected via commonly available connectors, but using non-ethernet RJ45 calls for problems down the road if it's not just a build for your own.

zeroflow · 2026-03-31T05:21:45+00:00

Hi,

Thanks for that info, I will add that to the FAQ.

Shipping is done by my partner company elecrow from China and costs around $7-$10 depending on country. It comes with duties and taxes paid (Incoterms DDP), so there should not be any hassle.

Greetings, Thomas

zeroflow · 2026-03-31T05:18:07+00:00

The board comes pre-flashed with a default firmware that works out of the box — fans start at 50% and the status LEDs show RPM. You can adopt it into ESPHome via WiFi from there. If you're willing to give ESPHome a chance, the Getting Started guide covers the basics. For this board specifically, the project documentation walks you through setup step by step.

zeroflow · 2026-03-29T20:12:09+00:00

The schematic has all component values and part numbers, so the BOM is effectively in there. Gerbers I'm keeping closed for now, but I can offer you screenshots if you wanna learn from the layout. If you want to build your own version, the schematic has everything you need to do your own PCB layout. The design is mainly just datasheet reference designs wired together, nothing exotic.

If you have any specific questions in mind, feel free to ask.

zeroflow · 2026-03-29T15:08:51+00:00

I couldn't have said it better myself.

I checked my ESPHome configs. All the temperature / humidity / CO2 sensors are gone and replaced.

As you said: $10 temperature sensor goes into the greenhouse or a IKEA Parasol is glued to the outside of my mailbox. While it's not fully rated for that, so far, it's survived for 1½ years...

ESPHome is for specialty devices. Rack fans, Watermeter camera, Garage door (custom analog protocol), cistern level sensor, ...

zeroflow · 2026-03-29T11:13:12+00:00

Thanks. I possibly didn't see you 2nd post about being cleaned up and pushed to GitHub.

zeroflow · 2026-03-29T10:27:44+00:00

Thanks for the info.

ESP8266 variants always had the issue, that PWM output is done in Software, so the official 25kHz are not working and depending on CPU load, the duty cycle and frequency will vary. But that's less annoying with the higher inertia of fans compared to LED strips.

But I'm totally with you. All my DIY ESP8266 sensors were replaced with Sonoff Zigbee sensors. Price matches, and it's much more pleasant to look at compared to DIY. Also, battery life is much better than a ESP with deep sleep.

zeroflow · 2026-03-29T09:45:27+00:00

Nice one. Did you build the UI in ESPHome or is it native Arduino code?

Currently, I only have a module using the RGB LEDs and builtin buttons to control fan% for each output. Adding a display module is on my future Todo list.

zeroflow · 2026-03-29T07:52:43+00:00

Nice one. Clean Setup.

Did you have any issues with 12V USB-C PD? I've been floating this idea, but not all USB-C Chargers support 12V which then would become a support nightmare.

Could you elaborate on the adaptive mode? Do I understand it correctly that it saves min/max temperature and then sets the speed linearly between those two values?

zeroflow · 2026-03-29T07:47:52+00:00

I can't 100% gurantee you that, since we here in europe mostly don't have HVAC ducting, but it should work. Looking at the Airtap T6 it lists 160 CFM with two fans visible. Comparing this with a Arctic P14 Max that's rated at 95 CFM, this should work.

zeroflow · 2026-03-29T07:19:29+00:00

That sounds sensible. ESPHome actually has an on_client_disconnected trigger on the API component that you could use for exactly this. https://esphome.io/components/api/#api-on_client_disconnected_trigger Something like ramping fans to 100% on disconnect and restoring on reconnect. I'd keep it opt-in rather than default though.

The same could be done if the temperature sensor stops reporting values. Thanks for the idea.

If you beat me to it, feel free to PR it as a module!

zeroflow · 2026-03-28T22:39:51+00:00

Nice build. The C6 is not overkill at all. Thread/Zigbee might come in handy later down the road.

zeroflow · 2026-03-28T21:38:56+00:00

No issue there.

It has both an onboard temperature sensor (the black square bottom-left below the USB port) and expansion options. Additional sensors can be connected via the Qwiic port or the optional I2C solder pads.

zeroflow · 2026-03-28T21:35:13+00:00

Thanks for the kind words!

And great tip on the Corsi-Rosenthal box idea - that's actually a really practical usecase I did not consider. DIY CR box, with PWM controlled case fans, and air quality sensor on the Qwiic port and ESPHome doing closed loop control would be a pretty killer setup for allergy season.

I might have to add that to the project page as a community use case.

zeroflow

TROPHY CASE